--- On Tue, 9/2/10, Anthony McKale <[email protected]> wrote: > From: Anthony McKale <[email protected]> > Subject: Re: [backstage] BBC Flash video and deinterlacing - is this really > the best we can get? > To: [email protected] > Date: Tuesday, 9 February, 2010, 10:48 > You'll find youtube has the same > problem > > http://www.youtube.com/watch?v=oHg5SJYRHA0 > > Ant > > > On 09/02/2010 00:51, "Christopher Woods" <[email protected]> > wrote: > > > I've noticed that for some reason blend deinterlacing > is still being used on > > all BBC Video footage (iPlayer, inline footage on > News/Sports sites, etc). > > It looks naff, causes image doubling in areas of high > movement and makes > > scrolling credits harder to read. (Also don't think it > looks as good and > > halves the perceived framerate) As reference, the > doubling is very > > noticeable on a recent episode of Hustle in the > 'action areas': > > http://i46.tinypic.com/14jxctd.png (a > deck of cards is being fountained > > upwards, falling down onto the camera - note the > overlapping ghosts of the > > moving cards). > > > > I first wondered if this was a limitation of how Flash > renders > > interlaced-encoded video, but I happened to be > watching a particular > > sporting event via an unofficial Justin.tv stream and > the motion was fluid > > and crisp. From that I can only assume all BBC videos > are encoded as > > progressive, and as such the Blend deinterlacing is > burnt in, with the same > > going for Live streams... If the content is being > deinterlaced from a > > broadcast source, why not use Bob or Weave? Blend just > looks awful, > > motorsports/action looks dire and even regular stuff > looks pants. > >
In the case of Youtube you don't know whether the user already uploaded it with blended fields. Youtube's ingest/encode chain is based on mencoder (a very old one at that) and if I remember rightly they use one of the deinterlacers built in to mencoder. Bob wouldn't be particularly useful because doubling the framerate, whilst making the image more fluid, would require higher system requirements. Weave would be worse than blending because it would leave combing artefacts everywhere. Flash doesn't have any deinterlacer built-in. There are plenty of free pixel-adaptive deinterlacers out there though such as Yadif or a decomb filter could be used. There are even some painfully slow motion compensated ones that would be probably be in the same league as expensive snell and wilcox equipment. - Sent via the backstage.bbc.co.uk discussion group. To unsubscribe, please visit http://backstage.bbc.co.uk/archives/2005/01/mailing_list.html. Unofficial list archive: http://www.mail-archive.com/[email protected]/
